User:ØverLørd/A Plotters Diary

another wiki page...

HP7475A

HP7475A undressed – It´s basically 3 motors, a solenoid some buttons and some computori bits

The buttons allow for intimate play with the plotter.

Drawings made using the button interface (Horse, Toilet, Robot (from top to bottom)), disregard the circles as they were not made with the buttons.(paper is precious)

Holding P1 and P2 while turning the machine on makes it plot a demo!
It is multicolor, but this was made with only 1 pen

Stonks are raising from the ashes of devastating financial crisis of 1981-82

parallel to serial to USB 2.0 to USB-c allows the plotter and computer to talk to each other

With HPGL incantations you can make the plotter make different shapes, lines and text.

With inkscape you can trace images, and turn vectors into HPGL.
Plotting around is the best way to understand the relation between screen and paper.

The plotter would randomly stop mid-plot, and the "error" light would start flashing.
The same file would stop at different times.

A byproduct of this are terminal logs like this:

Last login: Wed Oct 11 18:02:00 on ttys001
victor@MacBook-Pro ~ % ls
Applications			Sites
Creative Cloud Files		jagex_cl_oldschool_LIVE.dat
Desktop				jagexappletviewer.preferences
Documents			jagexcache
Downloads			osci-render
Library				plotting-venv
Movies				random.dat
Music				rotmg.xml
Pictures			rute3.png
Postman				rute5.png
Public				vegg.png
RealmOfTheMadGod
victor@MacBook-Pro ~ % source plotting-venv/bin/activate
(plotting-venv) victor@MacBook-Pro ~ % ls
Applications			Sites
Creative Cloud Files		jagex_cl_oldschool_LIVE.dat
Desktop				jagexappletviewer.preferences
Documents			jagexcache
Downloads			osci-render
Library				plotting-venv
Movies				random.dat
Music				rotmg.xml
Pictures			rute3.png
Postman				rute5.png
Public				vegg.png
RealmOfTheMadGod
(plotting-venv) victor@MacBook-Pro ~ % cd Desktop/Special\ Issue\ 22/plotterdokumentasjon
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % ls
machine.mov		plotteplott.ai		plotteplott2.svg
myfirsthpgl.hpgl	plotteplott.psd		plotterplott.hpgl
nonmachine.mov		plotteplott.svg		pp2.hpgl
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % chiplotle3 
 
  +-----------------------+
  |   Chiplotle! v.0.4.1  |
  +-----------------------+
 
Scanning serial ports...
Found ports:
  /dev/tty.JBLTUNE225TWS
  /dev/tty.Bluetooth-Incoming-Port
  /dev/tty.usbserial-110

Sniffing for plotters in all serial ports...
   Found plotter 7475A in port /dev/tty.usbserial-110

Instantiated plotter HP7475A in port /dev/tty.usbserial-110:
   Drawing limits: (left 0; bottom 0; right 16158; top 11040)
   Buffer Size: 512
chiplotle> plotter.write_file('pp2.hpgl')
HP7475A - WARNING - HPGL command ` ` not recognized by HP7475A. Command not sent.
Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 67, in write
    self._write_string_to_port(data)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 162, in _write_string_to_port
    raise TypeError('string expected.')
TypeError: string expected.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 109, in write_file
    self.write(comms)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 76, in write
    self._write_string_to_port(''.join(result))
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 166, in _write_string_to_port
    self._sleep_while_buffer_full( )
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 146, in _sleep_while_buffer_full
    while self._buffer_space < self.buffer_size:
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 196, in _buffer_space
    return int(bs)
ValueError: invalid literal for int() with base 10: '289\r\x00'
chiplotle> exit()
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % chiplotle3
 
  +-----------------------+
  |   Chiplotle! v.0.4.1  |
  +-----------------------+
 
Scanning serial ports...
Found ports:
  /dev/tty.JBLTUNE225TWS
  /dev/tty.Bluetooth-Incoming-Port
  /dev/tty.usbserial-110

Sniffing for plotters in all serial ports...
   Found plotter 7475A in port /dev/tty.usbserial-110

Instantiated plotter HP7475A in port /dev/tty.usbserial-110:
   Drawing limits: (left 0; bottom 0; right 16158; top 11040)
   Buffer Size: 512
chiplotle> plotter.write_file('pp3.hpgl')
HP7475A - WARNING - HPGL command ` ` not recognized by HP7475A. Command not sent.
^[[A^[[B^[[B^[[B^CTraceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 67, in write
    self._write_string_to_port(data)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 162, in _write_string_to_port
    raise TypeError('string expected.')
TypeError: string expected.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 180, in _read_port
    return self._serial_port.readline(eol='\r').decode('ascii') # <-- old pyserial
TypeError: readline() takes no keyword arguments

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 109, in write_file
    self.write(comms)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 76, in write
    self._write_string_to_port(''.join(result))
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 166, in _write_string_to_port
    self._sleep_while_buffer_full( )
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 146, in _sleep_while_buffer_full
    while self._buffer_space < self.buffer_size:
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 195, in _buffer_space
    bs = self._read_port()
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 182, in _read_port
    return self._serial_port.readline().decode('ascii')
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/serial/serialposix.py", line 565, in read
    ready, _, _ = select.select([self.fd, self.pipe_abort_read_r], [], [], timeout.time_left())
KeyboardInterrupt
chiplotle> exit(9
... exit()
  File "<stdin>", line 2
    exit()
    ^
SyntaxError: invalid syntax
chiplotle> exit()
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % chiplotle3
 
  +-----------------------+
  |   Chiplotle! v.0.4.1  |
  +-----------------------+
 
Scanning serial ports...
Found ports:
  /dev/tty.JBLTUNE225TWS
  /dev/tty.Bluetooth-Incoming-Port
  /dev/tty.usbserial-110

Sniffing for plotters in all serial ports...
   Found plotter 7475A in port /dev/tty.usbserial-110

Instantiated plotter HP7475A in port /dev/tty.usbserial-110:
   Drawing limits: (left 0; bottom 0; right 16158; top 11040)
   Buffer Size: 512
chiplotle> plotter.write_file('pp4.hpgl')
HP7475A - WARNING - HPGL command ` ` not recognized by HP7475A. Command not sent.
^CTraceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 67, in write
    self._write_string_to_port(data)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 162, in _write_string_to_port
    raise TypeError('string expected.')
TypeError: string expected.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 180, in _read_port
    return self._serial_port.readline(eol='\r').decode('ascii') # <-- old pyserial
TypeError: readline() takes no keyword arguments

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 109, in write_file
    self.write(comms)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 76, in write
    self._write_string_to_port(''.join(result))
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 166, in _write_string_to_port
    self._sleep_while_buffer_full( )
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 146, in _sleep_while_buffer_full
    while self._buffer_space < self.buffer_size:
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 195, in _buffer_space
    bs = self._read_port()
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 182, in _read_port
    return self._serial_port.readline().decode('ascii')
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/serial/serialposix.py", line 565, in read
    ready, _, _ = select.select([self.fd, self.pipe_abort_read_r], [], [], timeout.time_left())
KeyboardInterrupt
chiplotle> exit()
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % chiplotle3
 
  +-----------------------+
  |   Chiplotle! v.0.4.1  |
  +-----------------------+
 
Scanning serial ports...
Found ports:
  /dev/tty.JBLTUNE225TWS
  /dev/tty.Bluetooth-Incoming-Port
  /dev/tty.usbserial-110

Sniffing for plotters in all serial ports...
   Found plotter 7475A in port /dev/tty.usbserial-110

Instantiated plotter HP7475A in port /dev/tty.usbserial-110:
   Drawing limits: (left 0; bottom 0; right 16158; top 11040)
   Buffer Size: 512
chiplotle> plotter.write_file('pp5.hpgl')
HP7475A - WARNING - HPGL command ` ` not recognized by HP7475A. Command not sent.
Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 67, in write
    self._write_string_to_port(data)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 162, in _write_string_to_port
    raise TypeError('string expected.')
TypeError: string expected.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 109, in write_file
    self.write(comms)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 76, in write
    self._write_string_to_port(''.join(result))
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 166, in _write_string_to_port
    self._sleep_while_buffer_full( )
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 146, in _sleep_while_buffer_full
    while self._buffer_space < self.buffer_size:
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 196, in _buffer_space
    return int(bs)
ValueError: invalid literal for int() with base 10: '00\r\x00'
chiplotle> exit()
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % chiplotle3
 
  +-----------------------+
  |   Chiplotle! v.0.4.1  |
  +-----------------------+
 
Scanning serial ports...
Found ports:
  /dev/tty.JBLTUNE225TWS
  /dev/tty.Bluetooth-Incoming-Port
  /dev/tty.usbserial-110

Sniffing for plotters in all serial ports...
   Found plotter 7475A in port /dev/tty.usbserial-110

Instantiated plotter HP7475A in port /dev/tty.usbserial-110:
   Drawing limits: (left 0; bottom 0; right 16158; top 11040)
   Buffer Size: 512
chiplotle> plotter.write_file('pp5.hpgl')
HP7475A - WARNING - HPGL command ` ` not recognized by HP7475A. Command not sent.
^[[A^[[B^[[B^CTraceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 67, in write
    self._write_string_to_port(data)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 162, in _write_string_to_port
    raise TypeError('string expected.')
TypeError: string expected.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 180, in _read_port
    return self._serial_port.readline(eol='\r').decode('ascii') # <-- old pyserial
TypeError: readline() takes no keyword arguments

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 109, in write_file
    self.write(comms)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 76, in write
    self._write_string_to_port(''.join(result))
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 166, in _write_string_to_port
    self._sleep_while_buffer_full( )
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 146, in _sleep_while_buffer_full
    while self._buffer_space < self.buffer_size:
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 195, in _buffer_space
    bs = self._read_port()
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 182, in _read_port
    return self._serial_port.readline().decode('ascii')
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/serial/serialposix.py", line 565, in read
    ready, _, _ = select.select([self.fd, self.pipe_abort_read_r], [], [], timeout.time_left())
KeyboardInterrupt
chiplotle> exit()
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % chiplotle3
 
  +-----------------------+
  |   Chiplotle! v.0.4.1  |
  +-----------------------+
 
Scanning serial ports...
Found ports:
  /dev/tty.JBLTUNE225TWS
  /dev/tty.Bluetooth-Incoming-Port
  /dev/tty.usbserial-110

Sniffing for plotters in all serial ports...
   Found plotter 7475A in port /dev/tty.usbserial-110

Instantiated plotter HP7475A in port /dev/tty.usbserial-110:
   Drawing limits: (left 0; bottom 0; right 16158; top 11040)
   Buffer Size: 512
chiplotle> plotter.write_file('pp5_2.hpgl')
HP7475A - WARNING - HPGL command ` ` not recognized by HP7475A. Command not sent.
Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 67, in write
    self._write_string_to_port(data)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 162, in _write_string_to_port
    raise TypeError('string expected.')
TypeError: string expected.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 180, in _read_port
    return self._serial_port.readline(eol='\r').decode('ascii') # <-- old pyserial
TypeError: readline() takes no keyword arguments

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/serial/serialposix.py", line 575, in read
    buf = os.read(self.fd, size - len(read))
OSError: [Errno 6] Device not configured

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 109, in write_file
    self.write(comms)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 76, in write
    self._write_string_to_port(''.join(result))
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 166, in _write_string_to_port
    self._sleep_while_buffer_full( )
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 146, in _sleep_while_buffer_full
    while self._buffer_space < self.buffer_size:
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 195, in _buffer_space
    bs = self._read_port()
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 182, in _read_port
    return self._serial_port.readline().decode('ascii')
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/serial/serialposix.py", line 581, in read
    raise SerialException('read failed: {}'.format(e))
serial.serialutil.SerialException: read failed: [Errno 6] Device not configured
chiplotle> exit()
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % chiplotle3
 
  +-----------------------+
  |   Chiplotle! v.0.4.1  |
  +-----------------------+
 
Scanning serial ports...
Found ports:
  /dev/tty.JBLTUNE225TWS
  /dev/tty.Bluetooth-Incoming-Port
  /dev/tty.usbserial-110

Sniffing for plotters in all serial ports...
   Found plotter 7475A in port /dev/tty.usbserial-110

Instantiated plotter HP7475A in port /dev/tty.usbserial-110:
   Drawing limits: (left 0; bottom 0; right 16158; top 11040)
   Buffer Size: 512
chiplotle> plotter.write_file('pp5_2.hpgl')
HP7475A - WARNING - HPGL command ` ` not recognized by HP7475A. Command not sent.
Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 67, in write
    self._write_string_to_port(data)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 162, in _write_string_to_port
    raise TypeError('string expected.')
TypeError: string expected.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 109, in write_file
    self.write(comms)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 76, in write
    self._write_string_to_port(''.join(result))
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 166, in _write_string_to_port
    self._sleep_while_buffer_full( )
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 146, in _sleep_while_buffer_full
    while self._buffer_space < self.buffer_size:
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 196, in _buffer_space
    return int(bs)
ValueError: invalid literal for int() with base 10: '00\r\x00'
chiplotle> exit()
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % chiplotle3
 
  +-----------------------+
  |   Chiplotle! v.0.4.1  |
  +-----------------------+
 
Scanning serial ports...
Found ports:
  /dev/tty.JBLTUNE225TWS
  /dev/tty.Bluetooth-Incoming-Port
  /dev/tty.usbserial-110

Sniffing for plotters in all serial ports...
   Found plotter 7475A in port /dev/tty.usbserial-110

Instantiated plotter HP7475A in port /dev/tty.usbserial-110:
   Drawing limits: (left 0; bottom 0; right 16158; top 11040)
   Buffer Size: 512
chiplotle> plotter.write_file('pp5.hpgl')
HP7475A - WARNING - HPGL command ` ` not recognized by HP7475A. Command not sent.
^CTraceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 67, in write
    self._write_string_to_port(data)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 162, in _write_string_to_port
    raise TypeError('string expected.')
TypeError: string expected.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 109, in write_file
    self.write(comms)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 76, in write
    self._write_string_to_port(''.join(result))
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 166, in _write_string_to_port
    self._sleep_while_buffer_full( )
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 146, in _sleep_while_buffer_full
    while self._buffer_space < self.buffer_size:
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 195, in _buffer_space
    bs = self._read_port()
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 184, in _read_port
    time.sleep(sleep)
KeyboardInterrupt
chiplotle> exit()
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % chiplotle3
 
  +-----------------------+
  |   Chiplotle! v.0.4.1  |
  +-----------------------+
 
Scanning serial ports...
Found ports:
  /dev/tty.JBLTUNE225TWS
  /dev/tty.Bluetooth-Incoming-Port
  /dev/tty.usbserial-110

Sniffing for plotters in all serial ports...
   Found plotter 7475A in port /dev/tty.usbserial-110

Instantiated plotter HP7475A in port /dev/tty.usbserial-110:
   Drawing limits: (left 0; bottom 0; right 16158; top 11040)
   Buffer Size: 512
chiplotle> plotter.write_file('pp3.hpgl')
HP7475A - WARNING - HPGL command ` ` not recognized by HP7475A. Command not sent.
Traceback (most recent call last):
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 67, in write
    self._write_string_to_port(data)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 162, in _write_string_to_port
    raise TypeError('string expected.')
TypeError: string expected.

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 109, in write_file
    self.write(comms)
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 76, in write
    self._write_string_to_port(''.join(result))
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 166, in _write_string_to_port
    self._sleep_while_buffer_full( )
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 146, in _sleep_while_buffer_full
    while self._buffer_space < self.buffer_size:
  File "/Users/victor/plotting-venv/lib/python3.8/site-packages/chiplotle3/plotters/baseplotter.py", line 196, in _buffer_space
    return int(bs)
ValueError: invalid literal for int() with base 10: '00\r\x00'
chiplotle> exit()
(plotting-venv) victor@MacBook-Pro plotterdokumentasjon % 

By changing pens for each run you can see that it does not error at the same point. suggesting that it might be a hardware issue rather than software (maybe).

By simplifying the image one could easier keep track of what was going on, kinda.

Somtime around this point it became evident that the issue was that the roller that moves the paper would get internally stuck.

By making the images up of lines orthogonal to the papers movement, the strain on the roller was minimized thus leading to more successful plots.

Still it would throw an Error once in a while. To salvage a plot, one can guesstimate on how much of the HPGL has been run, and delete it from the file, before plotting again. This practice is not perfect hence, the doubled blue lines in a portion of this plot.

By splitting images into layers based on the color channels or thresholds, one can make low fidelity imagery some would say it has an "interesting aesthethic".

With a semi-reliable plotter at hand, the next task was to escape the prison of only being able to use, mostly green, small strange pens.

Some scotch-tape and Lærertyggis/tac-it, makes pretty much anything a pen-plotter-pen (weight is a limiting factor)

By taping the pen to the pen, it creates a doubled image with an offset. Crayons are cool^

Brush pens introduce something "organic" to the very machinic

it might be a bit messy, but only in the good way

Watercolors can be used

A parallel-pen makes the demo even more "artistic"